/*
 * ProGuard -- shrinking, optimization, obfuscation, and preverification of Java bytecode.
 *
 * Copyright (c) 2002-2018 GuardSquare NV
 *
 * This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public
 * License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later
 * version.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied
 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along with this program; if not, write to the Free
 * Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */
package proguard.optimize.peephole;

import proguard.classfile.*;
import proguard.classfile.util.SimplifiedVisitor;
import proguard.classfile.visitor.ClassVisitor;
import proguard.optimize.KeepMarker;

/**
 * This <code>ClassVisitor</code> makes the program classes that it visits final, if possible.
 *
 * @author Eric Lafortune
 */
public class ClassFinalizer extends SimplifiedVisitor implements ClassVisitor {
    private final ClassVisitor extraClassVisitor;

    /**
     * Creates a new ClassFinalizer.
     */
    public ClassFinalizer() {
        this(null);
    }

    /**
     * Creates a new ClassFinalizer.
     * 
     * @param extraClassVisitor an optional extra visitor for all finalized classes.
     */
    public ClassFinalizer(ClassVisitor extraClassVisitor) {
        this.extraClassVisitor = extraClassVisitor;
    }

    // Implementations for ClassVisitor.

    public void visitProgramClass(ProgramClass programClass) {
        // If the class is not final/interface/abstract,
        // and it is not being kept,
        // and it doesn't have any subclasses,
        // then make it final.
        if ((programClass.u2accessFlags
            & (ClassConstants.ACC_FINAL | ClassConstants.ACC_INTERFACE | ClassConstants.ACC_ABSTRACT)) == 0
            && !KeepMarker.isKept(programClass) && programClass.subClasses == null) {
            programClass.u2accessFlags |= ClassConstants.ACC_FINAL;

            // Visit the class, if required.
            if (extraClassVisitor != null) {
                extraClassVisitor.visitProgramClass(programClass);
            }
        }
    }
}
